ci: a runner label names the platform, not the org

hanzo-build-linux-amd64, lux-build-linux-amd64, zoo-build-linux-amd64 and
every other org-prefixed spelling all meant the same machine. Which org a
job belongs to does not change which host can build it, so the org bought
one pool name per org per arch and each could go stale on its own -- the
evo host alone answered to fourteen names for one label.

One vocabulary now: linux-amd64, linux-arm64, macos-arm64, win-amd64. The
generic labels every plain workflow uses (ubuntu-latest, self-hosted) are
untouched, so naive CI keeps working.

Co-authored-by: Hanzo Dev <[email protected]>

.hanzo/workflows/ci.yml

@@ -21,7 +21,7 @@ name: CI
 #
 # This replaces .github/workflows/validate-asset-manifests.yml, whose two jobs
 # named the bare `['self-hosted', 'linux', 'amd64']` triple. The pool on this
-# forge is `lux-build-linux-amd64`; nothing answers to the triple, and a job
+# forge is `linux-amd64`; nothing answers to the triple, and a job
 # naming a label no runner carries does not fail — it waits. So this gate has
 # not actually been gating anything.
 
@@ -53,7 +53,7 @@ env:
 
 jobs:
   registry-tests:
-    runs-on: [lux-build-linux-amd64]
+    runs-on: [linux-amd64]
     timeout-minutes: 30
     steps:
       - uses: actions/checkout@v4
@@ -66,7 +66,7 @@ jobs:
 
   live-validation:
     needs: registry-tests
-    runs-on: [lux-build-linux-amd64]
+    runs-on: [linux-amd64]
     timeout-minutes: 30
     strategy:
       fail-fast: false

.hanzo/workflows/release.yml

@@ -53,7 +53,7 @@ concurrency:
 
 jobs:
   plan:
-    runs-on: [lux-build-linux-amd64]
+    runs-on: [linux-amd64]
     timeout-minutes: 10
     outputs:
       images: ${{ steps.load.outputs.images }}
@@ -146,7 +146,7 @@ jobs:
     # Registry-side only: imagetools reads the two per-arch manifests and writes
     # a list that points at both. No builder and no platform of its own, so which
     # pool runs this does not matter.
-    runs-on: [lux-build-linux-amd64]
+    runs-on: [linux-amd64]
     timeout-minutes: 15
     steps:
       - name: Compute the release names

.hanzo/workflows/slot.yml

@@ -27,7 +27,7 @@ concurrency:
 
 jobs:
   slot:
-    runs-on: [lux-build-linux-amd64]
+    runs-on: [linux-amd64]
     timeout-minutes: 10
     steps:
       - uses: actions/checkout@v4